This invention relates generally to hand-held power tools, such as an electric planer, groover, jigsaw, router, trimmer, circular saw, cut-off machine and the like, having a slide base in contact with a surface of a work piece. More particularly, the present invention relates to a mechanism for guiding the tool body so as to travel straight with respect to the work piece.
When machining a work piece, such as a piece or board of wood, metal and concrete, with a hand-held power tool, it is important that the tool body moves straight along the surface of the work piece. For instance, if a planer is not moved straight, the blade thereof travels along a curve, machining the work piece in an undesirable manner. Namely, the blade of the tool is apt to slip off a given range on the surface of the work piece, and thus a portion of the surface of the work piece may be left unmachined. Furthermore, in the case of a groover or the like, the machined groove is apt to be undesirably curved due to nonstraight forwarding of the total.
Some conventional hand held tools are equipped with a guide piece for guiding the tool body parallel to the side of the work piece. However, attachment of the guide piece is troublesome. Also, entire tool including the guide piece is bulky and therefore often difficult to handle. Furthermore, when the size of the work piece is large, such a guide piece cannot be used. In addition, since such conventional guide pieces are arranged to be in contact with only one side of a work piece, the hand-held power tool equipped with the guide has to be moved by applying a force whose direction is slightly deviated from the straight forwarding direction so that the guide piece is always in contact with the side of the work piece.
For these reasons, such a conventional guide piece has not been used very much hitherto. Therefore, the user or operator of such a tool has to be very careful so that the tool slides straight on the surface of the work piece.